The abstract of the talk (see below) may be downloaded in one of the following formats:
The Zariski closure operator is naturally defined in any category of ``affine spaces" modelled over an algebra $A$. (See [1] and [2].) In this talk we look at the algebras on $A = \{0,1\}$ having arbitrary joins and $\alpha$-meets ($\alpha$ a regular cardinal) and the topological spaces {\bf Alex($\alpha$)} that they model. Using the Zariski closure we investigate separated objects, completion constructions and compactness properties in {\bf Alex($\alpha$)}. In this way a simple generalization gives rise to a wealth of interesting examples. \begin{thebibliography}{2} \bibitem{Diers99} Y.~Diers, {\em Affine algebraic sets relative to an algebraic theory,} Journal of Geometry, {\bf 65} (1999), 329-341. \bibitem{Giuli2000} E.~Giuli, {\em Zariski closure, completeness and compactness,} CatMAT 2000\\ Proceedings:Mathematik-Arbeitspapiere, Universit\"at Bremen, {\bf 54} (2000), 207--216. \end{thebibliography}